The traditional lab report as typically written by physics students is known to exhibit several deficiencies: Underdeveloped explanations of background material, incomplete reasoning to support results and conclusions, and vague demonstrations of student learning. We attribute such deficiencies to the inauthentic nature of the lab report, as it requires the student to repeat back to the instructor information the instructor already knows. We have found that replacing the traditional lab report with a Letter Home written to a non-physicist creates a more authentic post-lab writing experience, promotes a deeper “unlearning” process for students, and results in student writing that is more complete and of higher quality than the traditional lab report. We outline the structure of the Letter Home assignment, present several samples of student writing, and discuss an initial assessment of this assignment’s impact on student self-confidence.